Stereodivergent Access to Trisubstituted Alkenylboronate Esters through Alkene Isomerization.

We report an efficient method for the preparation of synthetically valuable trisubstituted alkenylboronate esters through alkene isomerization of their readily available 1,1-disubstituted regioisomeric counterparts. Either stereoisomer of the target alkenylboronate motif can be obtained at will from the same starting material by employing different isomerization catalysts.